return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) Standard Reference Database 101 National Institute of Standards and Technology
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Bad vibrational frequency predictions

Calculated frequencies that differ from experiment by more than 400 cm-1 or have a ratio with experiment outside of 0.7 to 1.2 are listed

Calculated vibrational frequencies ("theory" in table) are calculated at CCSD/6-31G*
Calculated values were scaled by 0.9443.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 330 130 0.606
C2H4+ Ethylene cation 4 Au 84 -199 -283 -0.423
C2H2 Acetylene 4 Πg 612 398 -214 1.537
CH3CCH propyne 10 E 328 253 -75 1.295
CHONH2 formamide 12 A" 289 -185 -474 -1.562
CBr2F2 Methane, dibromodifluoro- 3 A1 140 322 182 0.435
CH3COOCH3 methyl acetate 27 A" 110 65 -45 1.694
CF2CCl2 difluorodichloroethylene 7 B1 1327 553 -774 2.400
CF2CCl2 difluorodichloroethylene 8 B1 989 315 -674 3.139
CF2CCl2 difluorodichloroethylene 11 B2 564 440 -124 1.281
CF2CCl2 difluorodichloroethylene 12 B2 323 181 -142 1.780
C3H6O 2-Propen-1-ol 24 A 188 105 -83 1.794
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 328 -881 3.686
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 399 -134 1.336
C4H2 Diacetylene 7 Πg 482 333 -149 1.447
C4H2 Diacetylene 8 Πu 630 484 -146 1.301
C3H6O Oxetane 18 B1 90 -48 -138 -1.853
HCNO fulminic acid 5 Π 224 145 -79 1.547
C5H8 1,4-Pentadiene 16 A 137 286 149 0.479
HCCCl Chloroacetylene 5 Π 326 219 -107 1.490
C2F2 difluoroacetylene 4 Πg 270 210 -60 1.285
CaO Calcium monoxide 1 Σ 732 555 -177 1.319
NaOH sodium hydroxide 3 Π 300 134 -166 2.245
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 216 72 0.667
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 333 -123 1.369
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 109 -62 1.566
CH3 Methyl radical 2 A2" 606 410 -196 1.479
CH2OH Hydroxymethyl radical 8 A 482 702 220 0.686
CH2OH Hydroxymethyl radical 9 A 234 420 186 0.557
CHCl2 dichloromethyl radical 4 A' 190 296 106 0.642
C4H6 Methylenecyclopropane 17 B1 360 269 -91 1.338
C2Cl2 dichloroacetylene 4 Πg 333 184 -149 1.807
N2 Nitrogen diatomic 1 Σg 2359 1625 -733 1.451
D2O Deuterium oxide 1 A1 2671 3543 872 0.754
D2O Deuterium oxide 2 A1 1178 1649 471 0.715
D2O Deuterium oxide 3 B2 2788 3663 875 0.761
ZnCN Zinc monocyanide 3 Π 212 85 -127 2.505
N2O3 Dinitrogen trioxide 9 A" 63 134 71 0.470
Li2O dilithium oxide 3 Πu 112 71 -40 1.569
CaOH Calcium monohydroxide 2 Σ 353 604 251 0.584
CaOH Calcium monohydroxide 3 Π 609 376 -233 1.619
DS Mercapto-d 1 Σ 1886 2537 651 0.743
SF5Cl sulfur chloropentafluoride 5 B1 625 451 -174 1.386
SF5Cl sulfur chloropentafluoride 7 B2 505 310 -195 1.631
SF5Cl sulfur chloropentafluoride 11 E 397 243 -154 1.636
ZnH2 Zinc hydride 3 Πu 633 473 -160 1.337
C2H4O4 Formic acid dimer 13 Au 1050 66 -984 15.811
ClOO chloroperoxy radical 2 A' 414 909 496 0.455
Cl3- trichloride anion 2 Σu 327 223 -104 1.465
H2POH Phosphinous acid 9 A" 375 248 -127 1.511
Mg2 Magnesium diatomic 1 Σg 51 297 246 0.172
CH3BO Borane, methyloxo- 7 E 897 1432 535 0.626
ONONO Nitrosyl nitrite 9 B2 380 545 165 0.697